NMR of Microencapsulated Fish Oil Samples During In Vitro Digestion

Abstract

The use of nuclear magnetic resonance (NMR) spectroscopy for characterising microencapsulated tuna oil powders (25% and 50% w/w oil) and assessing the behaviour of the microcapsules on their exposure to water, simulated gastric fluid or to sequential exposure of simulated gastric and intestinal fluids was examined. The matrices used for encapsulation were physical mixtures of casein or whey protein in combination with carbohydrates (dextrose monohydrate with either dried glucose syrup or a physically modified resistant starch) or heated mixtures of these matrices. Solid-state 13 C cross-polarised magic angle spinning NMR and dipolar de-coupled magic angle spinning NMR record the 13 C NMR signals of the encapsulant material and that of the encapsulated oil, respectively. 1 H and 13 C solution NMR were used to investigate the relative increase in mobility of the various encapsulant matrices due to their dissolution on exposure to gastrointestinal fluids. The results suggested that the dissolution characteristics of matrices of microencapsulated oil powders were dependent on the type of milk protein and carbohydrate used and whether the protein-carbohydrate matrices were heat-treated prior to encapsulation of the oil.

Effects of microencapsulation on the gastrointestinal transit and tissue distribution of a bioactive mixture of fish oil, tributyrin and resveratrol

“…The peak at 0.25-0.3 lm represents the oil droplets while that at 7-9 lm is the modified resistant starch component. A bi-modal peak distribution with similar features has been previously observed for all fish oil-in-water emulsions made with the same encapsulant components at the same oil:encapsulant ratio of emulsions made with resistant starch (Burgar, Hoobin, Weerakkody, Sanguansri, & Augustin, 2009;Oliver, Augustin, & Sanguansri, 2009). …”

Flaxseed Oil Microcapsules Prepared Using Soy Protein Isolate and Modified Starch: Process Optimization, Characterization and In Vitro Release Behaviour

“…Gastrointestinal conditions were simulated where both gastric conditions (SGC) alone and a combination of SGC and simulated intestinal conditions (SIC) were created to study the release pattern of flaxseed oil from the microcapsules in human digestive tract according to the method given by Burgar et al [5]. The per cent flaxseed oil release in gastrointestinal condition was measured by sub-sequential exposure of microcapsules to SGC and SIC for 3 and 2 h, respectively.…”

Tuna red meat hydrolysate as core and wall polymer for fish oil encapsulation: a comparative analysis

“…In vitro oil release kinetics using simulated gastro-intestinal fluids were studied by the methodology described by Burgar et al (2009). A known quantity of oil encapsulates were initially subjected to gastric digestion using simulated gastric fluid (SGF) containing pepsin at 37 °C for 2 h under acidic condition (pH 1.2).…”